I strained mine a few months ago when I found myself too far back on the belt while running on a treadmill. My foot drop off the end, and while I recovered without wiping out, I hyperextended my hip in the process. I proceeded to finish my run with only a small amount of "managable" discomfort. The next day it was sore, but not painful. This subsided by the second day, and felt pretty much normal walking around, stretching, etc. On my next run, the second day after the incident, it started out feeling fine, but as I increased my pace, it started to feel more and more uncomfortable.

I stupidly repeated this process of running every other day for about week, and each workout became progressively more painful. At that point, I smartly (finally) concluded I was gradually doing more and more damage with each run, so I took 2 weeks off. Came back gradually, but the discomfort quickly returned, and progressed even more quickly than the first go round. Honestly, at that point, I was a little concerned that I had more of a problem than just a simple strain.

After a bit of reading, source after source stated that this injury requires a 5 week off period to resolve. This seemed excessive to me, because my hip would always feel perfectly fine with nearly every non-running activity (this is why the injury is so tricky), but I did just that - took exactly 5 weeks off running. I continued doing everything that produced NO pain and NO discomfort, like swimming and my elliptical trainer.

Then after the 5 weeks I began a VERY slow and cautious comeback, and that was the last of it. Now though, I am diligent about warm up and stretching the hips (along with other bits), but (knocks on wood) there have been no signs of any discomfort since.

After a bit of reading, source after source stated that this injury requires a 5 week off period to resolve. This seemed excessive to me, because my hip would always feel perfectly fine with nearly every non-running activity (this is why the injury is so tricky), but I did just that - took exactly 5 weeks off running. I continued doing everything that produced NO pain and NO discomfort, like swimming and my elliptical trainer.

Most of what I read gave recovery ranges of 3-8 weeks depending on the severity of the injury. If I recall, they assigned levels from 1-3, with 1 being very minor and 3 very severe. They described 1 as taking a few days and 3 being season or possibly career ending.

Based on my symptoms and level of pain/discomfort, I rated my injury a 2 on that scale, and elected to take the 5 weeks since it was right in the middle of all the ranges. If I still had issues after that, my plan was to see a professional, but luckily I haven't had any more trouble. Could I have gotten by with less time off? Maybe..

Short of seeing your doctor, there are several helpful websites that can help with some insight.

oh man. I"ve been there before. I did 4 tris in 3 days and the following day I was trying to dig up a plant. I think the shovel did the damage with tight muslces. ART helped tremendously, but it took a little over 2 months to disappear. It was getting better and 5 days before the IM I hopped in the car and felt the pain again. The day before the IM I got a massage and that didn't help. I decided to try one last ART treatment and I could feel a diffeence. The next day was the IM and I raced. Never had the issue again. Really weird I know! The only other thing I felt that helped the issue besides ART was laying on a trigger ball and rolling. Good luck

After a bit of reading, source after source stated that this injury requires a 5 week off period to resolve. This seemed excessive to me, because my hip would always feel perfectly fine with nearly every non-running activity (this is why the injury is so tricky), but I did just that - took exactly 5 weeks off running. I continued doing everything that produced NO pain and NO discomfort, like swimming and my elliptical trainer.

I had the exact same issue. I was ramping up run mileage and had some discomfort in the hip.
I thought it was a BRic issue, but hip wouldn't hurt on the bike.
My hip would act up about 3 miles into a run. Imagine being 3 miles into a 12 mile and a total breakdown happens. Ugh.
I struggled on the run of my last Tri.
I had to cancel all running events in oct and nov.
2 different chiros - both runners, tried to relax the flexor, to no avail.
A sports therapist sent for a MRI to determine if there was a stress fracture. Not a fracture, not tendinitis .. Just a very bad flexor.
5 weeks of no running.
I swan, and biked a ton. I am now back to running about 5 or 6 miles.
I have incorporated yoga and a bunch of hip strength exercises in the routine.
Hope this helps.

I don't think I had it as bad as you, but recently while trying to fix my it, I foam rolled my hip flexor muscles and they were ever so tight. I think because I was doing yoga for it but it definitely helped me.